Project description:Sorption mechanism of uranyl by poly(bis[2-(methacryloyloxy)ethyl] phosphate) (PB2MP) functionalised polyvinylidene fluoride (PVDF) track-etched membranes, PB2MP-g-PVDF, was investigated. It was found that uranyl sorption obeyed Langmuir isotherm model giving a maximum U(VI) membrane uptake of 6.73 μmol g-1 and an affinity constant of 9.85 ⋅ 106 L mol-1. XPS and TRPL measurements were performed to identify sorbed uranyl oxidation state and its environment. Uranyl was found to be mainly in its hexavalent state, i.e. U(VI), showing that the trapping inside the PB2MP-g-PVDF nanoporous membranes did not change the ion speciation. Two sorbed uranyl life-times (τ1 = 8.8 μs and τ2 = 102.8 μs) were measured by TRPL which pointed out different complexations taking place inside the nanopores. Uranyl sorption by PB2MP-g-PVDF membranes was also found to be pH dependent demonstrating the highest performance at circumneutral pH. In addition, TRPL was demonstrated to be not only a remarkable technique for U(VI) characterization, but also an alternative to voltammetry detection for trace on-site uranyl monitoring using PB2MP-g-PVDF nanoporous membranes.
Project description:A two-dimensional (2D) material placed on an atomically flat substrate can lead to the formation of surface nanobubbles trapping different types of substances. In this paper graphene nanobubbles of the radius of 7-34 nm with argon atoms inside are studied using molecular dynamics (MD). All modeled graphene nanobubbles except for the smallest ones exhibit an universal shape, i.e., a constant ratio of a bubble height to its footprint radius, which is in an agreement with experimental studies and their interpretation using the elastic theory of membranes. MD simulations reveal that argon does exist in a solid close-packed phase, although the internal pressure in the nanobubble is not sufficiently high for the ordinary crystallization that would occur in a bulk system. The smallest graphene bubbles with a radius of 7 nm exhibit an unusual "pancake" shape. Previously, nanobubbles with a similar pancake shape were experimentally observed in completely different systems at the interface between water and a hydrophobic surface.
Project description:This paper studies a reliable facility location problem with facility protection that aims to hedge against random facility disruptions by both strategically protecting some facilities and using backup facilities for the demands. An Integer Programming model is proposed for this problem, in which the failure probabilities of facilities are site-specific. A solution approach combining Lagrangian Relaxation and local search is proposed and is demonstrated to be both effective and efficient based on computational experiments on random numerical examples with 49, 88, 150 and 263 nodes in the network. A real case study for a 100-city network in Hunan province, China, is presented, based on which the properties of the model are discussed and some managerial insights are analyzed.
Project description:Compartmentalization of chemical reactions inside cells are a fundamental requirement for life. Encapsulins are self-assembling protein-based nanocompartments from the prokaryotic repertoire that present a highly attractive platform for intracellular compartmentalization of chemical reactions by design. Using single-molecule Förster resonance energy transfer and 3D-MINFLUX analysis, we analyze fluorescently labeled encapsulins on a single-molecule basis. Furthermore, by equipping these capsules with a synthetic ruthenium catalyst via covalent attachment to a non-native host protein, we are able to perform in vitro catalysis and go on to show that engineered encapsulins can be used as hosts for transition metal catalysis inside living cells in confined space.
Project description:This qualitative study identified a study area by visualizing one year of animal intake from a municipal animal shelter on geographic information systems (GIS) maps to select an area of high stray-dog intake to investigate. Researchers conducted semi-structured interviews with residents of the selected study area to elucidate why there were high numbers of stray dogs coming from this location. Using grounded theory, three themes emerged from the interviews: concerns, attitudes, and disparities. The residents expressed concerns about animal welfare, personal safety, money, and health. They held various attitudes toward domestic animals in the community, including viewing them as pets, pests, or useful commodities (products). Residents expressed acceptance as well as some anger and fear about the situation in their community. Interviewees revealed they faced multiple socioeconomic disparities related to poverty. Pet abandonment can result when pet owners must prioritize human needs over animal needs, leading to increased shelter intake of stray dogs. Community-specific strategies for reducing local animal shelter intake should address the issue of pet abandonment by simultaneously targeting veterinary needs of animals, socioeconomic needs of residents, and respecting attitude differences between residents and shelter professionals.
Project description:IntroductionTraditionally, men are not supposed to take part in maternal health issues in many cultures. Nevertheless, pregnancy care and childbirth are the most crucial matters of reproductive health influenced by men. Hence, the aim of this study was to identify individual, sociocultural, and health facility factors affecting men's involvement in facility-based childbirth in Southwest, Ethiopia.ObjectivesThe aim of this study was to identify individual, sociocultural, and health facility factors affecting men's involvement in facility-based childbirth in Southwest, Ethiopia.MethodsA community-based cross-sectional study accompanied with a qualitative method was carried out from 1 July to 30 August 2019. A multistage cluster sampling technique was employed to recruit study participants. Descriptive statistics, frequencies, proportions, and mean were calculated, and the results of the analysis were presented in text, tables, and graphs. A multivariate logistic regression model was fitted to investigate the independent effect of each explanatory variable on the likelihood of men's involvement in facility-based childbirth. Qualitative data were analyzed thematically using OpenCode 4.0 software.ResultsOut of 800 men, only 36.5% (95% confidence interval: 33.3%-39.6%) were found to have involved in facility-based childbirth. Several factors were associated with men's involvement in facility-based childbirth of this, being in the age group of 40-49 (adjusted odds ratio 5.04, 95% confidence interval: 2.49-10.20), attaining secondary education and above (adjusted odds ratio 2.14, 95% confidence interval: 1.53-5.60), and having sufficient knowledge of danger signs during pregnancy (adjusted odds ratio 5.65, 95% confidence interval: 3.25-7.46) associated with men's involvement in facility-based childbirth.ConclusionRelevant entities had better design-specific educational programs targeting younger age groups, those with lower schooling, and had previous bad obstetrics outcomes. Involving elders and religious leaders in the reproductive health program could also help in overcoming the existing cultural barriers. Moreover, creating a men-friendly facility environment and extensively engaging medias are suggested to improve men's involvement in the study area.